2003-04 Mach 1 Registry Owners Club

2003-04 Mach 1 Registry Owners Club (http://www.mach1registry.org/forums/index.php)
-   Engine & Drivetrain (Including trans & rear axles) (http://www.mach1registry.org/forums/forumdisplay.php?f=64)
-   -   Fails to start when outside temps over 100 (http://www.mach1registry.org/forums/showthread.php?t=136130)

rsnider 08-09-2017 07:18 PM

Fails to start when outside temps over 100
 
I've been dealing with this dang issue for two years now. When the temperature is over 100 degrees outside the Mach won't start. If I let her sit until evening when the temps drop she will run. Except for yesterday. It was about 110 here in Phoenix and I pulled her out of the garage to do some cleaning up. About 2pm I went to pull her back inside and she cranks and spits a couple of times but won't start.
My mechanic replaced some sort of vacuum switch under the hood and the fuel module in the trunk. It's been find for six months, but I just don't drive her much in the summer.
Anyone who has had a similar issue please HELP.

DSG2003Mach1 08-09-2017 08:04 PM

Re: Fails to start when outside temps over 100
 
sounds like they replaced the FPDM which Ive seen people say was the cause for issues like this in the past. Did they replace it with a new one or a used one? If its used it may have failed as well is my first thought

rsnider 08-10-2017 12:48 AM

Re: Fails to start when outside temps over 100
 
New.

DSG2003Mach1 08-10-2017 08:52 AM

Re: Fails to start when outside temps over 100
 
at this point I would be suspecting the fuel pump but really all I can think of is to trouble shoot when it wont start.

When everything is normal if you turn the key to the run position can you hear the fuel pump prime for a few seconds? If so I would try this when it wont start and see if you can hear the pump prime. If not then you basically need a second person - use a volt meter and check the plug going OUT of the FPDM (have someone else turn the key forward and see if the pin(s) that power the fuel pump are getting proper voltage). If theres no power going out to the pump its going to have be traced further up the line. If there is voltage then it would basically have to be the pump

311-420 08-10-2017 10:26 AM

Re: Fails to start when outside temps over 100
 
Quote:

Originally Posted by DSG2003Mach1 (Post 1628057)
at this point I would be suspecting the fuel pump but really all I can think of is to trouble shoot when it wont start.

When everything is normal if you turn the key to the run position can you hear the fuel pump prime for a few seconds? If so I would try this when it wont start and see if you can hear the pump prime. If not then you basically need a second person - use a volt meter and check the plug going OUT of the FPDM (have someone else turn the key forward and see if the pin(s) that power the fuel pump are getting proper voltage). If theres no power going out to the pump its going to have be traced further up the line. If there is voltage then it would basically have to be the pump

This. Still the original pump?

mikeracing 08-11-2017 09:12 AM

Re: Fails to start when outside temps over 100
 
The only fuel module in the trunk is the roll over switch. The fpdm is in the right front fender i thought

DSG2003Mach1 08-11-2017 10:43 AM

Re: Fails to start when outside temps over 100
 
Quote:

Originally Posted by mikeracing (Post 1628087)
The only fuel module in the trunk is the roll over switch. The fpdm is in the right front fender i thought

nope, the cutoff that activates in a roll over/crash and the FPDM are in the trunk - behind the driver side panel. The CCRM is in the pass front fender behind the wheel liner

rich1 08-14-2017 01:05 AM

Re: Fails to start when outside temps over 100
 
Check all harness grounds heat can expand connection and fail. Fuel pump getting ready to fail also suspect.


All times are GMT -4. The time now is 04:55 AM.

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
(c) 2002-2013 Mach1Registry.com